Fixing bandwidth BR1

I have a ipad which needs his own secured wifi surroundings on my BR1. Now I know I’m not able to assign bandwith to a specific ipadres. But I want a the ipad to always be able to connect to the internet. On the br1 I have also a public wifi access and I want them not to be able to use all bandwidth. Could somebody please let me know how to set that up.
I’m not able to find it anywhere.

I know bits and pieces, but I’m not able to connect the dots, sort of speaking.

Thanx, Jeroen